4-VL is four-valued logic and pronounced "four-dash- vee-ell" or "four-vee-ell".

4-VL is based on four-valued bit code (4VBC) that names 00, 01, 10, 11 for contradiction, true, false, and tautology.

This site contains information about software applications and hardware implementations of 4VBC.

For the theory of 4VBC and how it applies to the propositional, modal, deontic, predicate, and polyadic logic segments, please see: 4VBC.com

For the open standard of 4VBC, working groups, meetings, and conferences, please see 4-VL.org when hosted soon.

There are papers here about using 4VBC to prove, explain, and show all sorts of things.

In Naha, Japan on May 20, 2009, this compressed file contains the contents of the CD distributed.

There is the seminal paper from the 8th International Conference on Boolean Problems, September 2008 in Freiberg (Sachsen), Germany, titled "Logical Foundations of Four Valued Bit Code (4VBC)".

There is an executable program generating the 256 look up tables (LUTs) for operators in 4VBC, some of which are not as yet named or labeled, and a sorted listing of LUTs.

There are notes about how in quantum computing 4VBC can map the gates of C-NOT, De utsch, Fredkin, and Toffoli.

There is a Statement of Work (SOW) for implementing 4VBC in computer hardwired devices.

There is a draft paper about how to map software loops and flows into 4VBC for the validation and verification of software correctness and suitability.

There are papers about multi-valued logics that show how 4VBC maps them and isolates their mistakes: CJ[09.8]; CJ[09.9]; and CJ[09.10].

There is also a proof of the existence of God in 4VBC.